import java.util.*;

public class ArrayListMagnet {
	
	public static void printAL(ArrayList<String> al){
		for(String element : al){
			System.out.print(element + " ");
		}
		System.out.println(" ");
	}

	
	public static void main(String[] args) {
	ArrayList<String> a = new ArrayList<String>();
	a.add(0, "zero");
	a.add(1,"one");
	a.add(2,"two");
	a.add(3,"three");
	printAL(a);
	a.remove(2);
	if(a.contains("three")){
		a.add("four");
	}
	printAL(a);
	if(a.indexOf("four")!=4){
		a.add(4, "4.2");
	}
	printAL(a);
	if(a.contains("two")){
		a.add("2.2");
	}
	printAL(a);
	}

}
